Flexible printed circuit boards that include a flexible base film and conductive patterns disposed on a front surface and a back surface of the flexible base film are used as printed circuit boards.
In flexible printed circuit boards, flexibility decreases in portions subjected to plating, and thus the area subjected to plating is preferably as small as possible. Therefore, in such a flexible printed circuit board, pattern plating is usually performed, and land parts are formed by this plating together with through-holes and blind via-holes (refer to, for example, Patent Literature 1).